Improvement in histology, enzymatic activity, and redox state of the liver following administration of Cinnamomum zeylanicum bark oil in rats with established hepatotoxicity

Inhibitory effect of temozolomide on apoptosis induction of cinnamaldehyde in human glioblastoma multiforme T98G cell line

Glioblastoma is the most common primary malignant brain tumor in adults. Temozolomide (TMZ) is an FDA-approved drug used to treat this type of cancer. Cinnamaldehyde (CIN) is a derivative of cinnamon extract and makes up 99% of it. The aim of this study was to investigate the in vitro combined effect of CIN and TMZ on human glioblastoma multiforme T98G cell line viability. In this study, we used 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyl-tertazolium bromide (MTT) method to evaluate the extent of IC50, acridine orange, Giemsa and Hoechst staining to evaluate the manner of apoptosis and the Western blotting method to examine the expression change of apoptotic proteins. Our results show that TMZ has an inhibitory effect on CIN when both used in combination at concentrations of 300 and 100 μM (P<0.05) and has a cytotoxic effect when used alone at the same concentrations (P<0.05). The western blotting result showed that TMZ at concentrations of 2,000 and 1,000 μM significantly increased Bax expression and decreased Bcl2 expression (P<0.05), indicating that TMZ induced apoptosis through the mitochondrial pathway. However, CIN had no effect on Bax and Bcl2 expressions, thus causing apoptosis from another pathway. Also, the Bax:Bcl2 expression ratio at concentrations combined was lower than that for TMZ 1,000 μM and higher than that for CIN 150 and 100 μM (P<0.05), which confirms the inhibitory effect of TMZ on CIN. From the present study, we conclude that TMZ in combination with CIN has an inhibitory effect on increasing the cytotoxicity rate.

Protective effect of cinnamon on diabetic cardiomyopathy in nicotinamide-streptozotocin induced diabetic rat model

There is an increase in the incidence and prevalence of type-2 diabetes and obesity which leads to the structural and functional changes in myocardium leading to a lethal complication called diabetic cardiomyopathy (DCM). In the present study, we investigated the preventive effect of cinnamon (3% of Cinnamomum zeylanicum bark powder in AIN-93 diet for 3 months) feeding on DCM and the concerned mechanisms in a rodent model. Experimental diabetes was induced by a single intraperitoneal injection of 40 mg/kg b.w streptozotocin (STZ), 15 min after the ip administration of 60 mg/kg b.w of nicotinamide (NA) in Wistar-NIN (WNIN) male rats. The oxidative stress parameters were investigated by assessing superoxide dismutase (SOD), glutathione-s-transferase (GST) enzyme activity, protein carbonyls and malondialdehyde (MDA) levels. The histopathology of myocardium was analyzed by H&E and Masson's trichrome staining, and scanning electron microscopy. The changes in diabetic rat heart involved the altered left ventricular parietal pericardium, structural changes in myocardial cells, enhanced oxidative stress. Masson's trichrome and H&E staining have shown increased fibrosis, and perinuclear vacuolization in NA-STZ induced diabetic rat myocardium. Cinnamon feeding prevented the oxidative stress and myocardial alterations in the heart of diabetic rats. Taken together, these results suggest that cinnamon can effectively prevent the metabolic and structural changes in NA-STZ induced diabetic cardiomyopathy.

Cinnamon and its possible impact on COVID-19: The viewpoint of traditional and conventional medicine

The COVID-19 global epidemic caused by coronavirus has affected the health and other aspects of life for more than one year. Despite the current pharmacotherapies, there is still no specific treatment, and studies are in progress to find a proper therapy with high efficacy and low side effects. In this way, Traditional Persian Medicine (TPM), due to its holistic view, can provide recommendations for the prevention and treatment of new diseases such as COVID-19. The muco-obstruction of the airway, which occurs in SARS-CoV-2, has similar features in TPM textbooks that can lead us to new treatment approaches. Based on TPM and pharmacological studies, Cinnamomum verum (Darchini)'s potential effective functions can contribute to SARS-CoV-2 infection treatment and has been known to be effective in corona disease in Public beliefs. From the viewpoint of TPM theories, Cinnamon can be effective in SARS-CoV-2 improvement and treatment through its anti-obstructive, diuretic, tonic and antidote effects. In addition, there is pharmacological evidence on anti-viral, anti-inflammatory, antioxidant, organ-o-protective and anti-depression effects of Cinnamon that are in line with the therapeutic functions mentioned in TPM.Overall, Cinnamon and its ingredients can be recommended for SARS-CoV2 management due to multi-targeting therapies. This review provides basic information for future studies on this drug's effectiveness in preventing and treating COVID-19 and similar diseases.

The methanolic extract of Cinnamomum zeylanicum bark improves formaldehyde-induced neurotoxicity through reduction of phospho-tau (Thr231), inflammation, and apoptosis

Accumulation of formaldehyde (FA) in the brain is linked to age-related neurodegenerative disorders, as it accelerates memory impairment through tau protein aggregation, inflammation, and nuclear damage. This study aimed to assess the possible effects of methanolic cinnamon extract (CE) on FA-induced neurotoxicity in rats. The animals were treated with CE (100, 200, and 400 mg/kg, P.O.) for 30 days following FA administration (60 mg/kg, I.P.) for 30 days. Briefly, spatial and inhibitory memory were examined by Morris water maze (MWM) and passive avoidance (PA) tasks, respectively. The Nissl, Hoechst, and Bielschowsky silver staining methods were also used to assess apoptosis and neurofibrillary tangles (NFTs) in the hippocampal CA1 region, respectively. Brain tissues were probed with an anti-phospho-tau (Thr²³¹) monoclonal antibody to assess tau hyperphosphorylation. Inflammatory cytokines (IL-1β, IL-6, and TNF-α) were also measured by ELISA assay. Western blotting was performed to quantify the amount of phospho-tau (Thr²³¹), caspase-8, and caspase-9. The results showed that FA injection significantly caused tau hyperphosphorylation at Thr²³¹ residue, which in turn disturbed the MWM performance. The ratio of apoptotic to intact neurons increased following FA treatment. The results of Western blotting indicated that the hippocampal levels of phospho-tau (Thr²³¹) and caspase-8 were significantly higher in the FA group compared to the control group. The hippocampal levels of IL-1β, IL-6, and TNF-α in the FA group were also higher than the control group. Administration of 200 mg/kg of CE significantly improved the rats' MWM performance, decreased the levels of phospho-tau (Thr²³¹), caspase-8, IL-6, and TNF-α, and reduced the ratio of apoptotic to intact neurons. Overall, cinnamon improved cognitive performance in FA-treated rats by eliminating tau hyperphosphorylation, inflammatory cytokines, and nuclear damage.

Potential role of cinnamaldehyde and costunolide to counteract metabolic syndrome induced by excessive fructose consumption

Background

One of the serious public health problems in the world is metabolic syndrome. It includes visceral obesity, dyslipidemia, insulin resistance, hyperglycemia, and hypertension. As a contributor to almost all the classic signs of metabolic syndrome, fructose was the ideal choice. There are certain shortcomings with existing drugs for insulin-resistant treatment. Plants still represent the main source of most available medicines. Cinnamaldehyde (CNA) is an active principle of Cinnamomum zeylanicum. Costunolide (CE) is natural sesquiterpene lactones, which is the main bioactive constituent of Saussurea lappa. The main aim of the present study is to investigate the effect of the synthetic antidiabetic agent (metformin) in comparison with natural constituents (cinnamaldehyde, costunolide) after developing a reliable model for insulin resistance by using high fructose diet (HFD).

Results

It was found that HFD increased plasma glucose, insulin, glycosylated hemoglobin, HbA1c, serum total cholesterol, LDL-cholesterol, triglyceride, ALT, AST, creatinine, and uric acid. Moreover, HFD decreased hepatic reduced glutathione and superoxide dismutase levels. While oral administration of cinnamaldehyde and costunolide significantly decreased plasma glucose, HbA1c, total cholesterol, LDL-cholesterol, triglyceride, and increased level of hepatic reduced glutathione and superoxide dismutase activity. Also, cinnamaldehyde and costunolide restored the altered plasma levels of ALT, AST, creatinine, and uric acid to normal.

Conclusions

The results of this experimental study showed that cinnamaldehyde and costunolide could be used as safe drugs for treating different abnormalities of metabolic syndrome.